: Apply a light coat of oil to the bolt carrier group and the inside of the receiver rails. Avoid over-lubricating, which can attract debris. Safety Precautions

Even reliable rifles malfunction. Below is a troubleshooting table derived from the official manual’s "Remedies" section.

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PTR PTR-91 A3SK .308 16in 20+1 Semi-Auto Rifle - Alexander's Store

Before cleaning, field stripping is mandatory. Here is the procedure exactly as outlined in the PTR 91 manual:

unless you have advanced gunsmithing experience. The PTR 91 manual explicitly warns that the trigger housing contains springs under tension that are difficult to reassemble without jigs.

Tilt the lower receiver (trigger pack) downward and remove it from the rifle.